A conveyor chain with rollers, which travel while rolling on a conveyor line, has been generally used for conveying transfer articles to a remotely set transfer position. Abrasion sensing means for such a conventional conveyor chain, which senses an abrasion in a roller, a bush and a pin, has been known (see, for example, Japanese Laid-Open Patent Publication No. H10-300426).
However, since in the above-mentioned abrasion sensing device of a roller chain, one end side of a pin in a roller chain is first imaged, then the center position of an image of the pin and the center position of an image of the associated roller is calculated, then a deviation between their both calculated center positions is obtained and abrasions in the roller and the like are sensed based on the obtained deviation, a high accuracy sensor and a highly developed image processing putting a CPU into full use is required. Thus although such a type of the abrasion sensing device can be used in a test room or the like, the setting up of a large-scale abrasion sensing equipment is required for adapting the abrasion sensing device to a conveyor chain set up at an actual conveying operation site and there were troublesome problems in maintenance with the result that highly advanced knowledge and operations for the image processing and the like are needed.